Chemical and Structural Insights into the Regioversatility of the Aminoglycoside Acetyltransferase Eis
Chemical and Structural Insights into the Regioversatility of the Aminoglycoside Acetyltransferase Eis
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DOI：
10.1002/cbic.201300359
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发表时间：
2013-11-04
期刊：
影响因子：
3.2
通讯作者：
Garneau-Tsodikova, Sylvie
中科院分区：
文献类型：
--
作者：
Houghton, Jacob L.;Biswas, Tapan;Garneau-Tsodikova, Sylvie
最近发现的结核病对最后一种药物氨基糖苷类卡那霉素耐药性的原因，是由于这种药物被增强的细胞内存活（Eis）蛋白修饰所致。EIS是一种结构和功能独特的乙酰转移酶，具有在多个位置乙酰化氨基糖苷类的不寻常能力。这种区域过度饱和的程度及其定义蛋白质的特征尚不清楚。在此，我们确定了五个氨基糖苷类化合物的乙酰化的位置和顺序的NMR光谱。该分析揭示了卡那霉素、阿米卡星和妥布霉素的3-胺以及阿米卡星的4-氨基-2-羟基丁酰基的-胺的前所未有的乙酰化。Eis与辅酶A和妥布霉素复合的晶体结构揭示了妥布霉素如何以两种结合模式容纳在Eis活性位点中，与其二乙酰化一致。这些研究描述了乙酰化的化学和结构细节，将指导未来设计氨基糖苷类和Eis抑制剂以克服结核病耐药性的努力。
A recently discovered cause of tuberculosis resistance to a drug of last resort, the aminoglycoside kanamycin, results from modification of this drug by the enhanced intracellular survival (Eis) protein. Eis is a structurally and functionally unique acetyltransferase with an unusual capability of acetylating aminoglycosides at multiple positions. The extent of this regioversatility and its defining protein features are unclear. Herein, we determined the positions and order of acetylation of five aminoglycosides by NMR spectroscopy. This analysis revealed unprecedented acetylation of the 3-amine of kanamycin, amikacin, and tobramycin, and the -amine of the 4-amino-2-hydroxybutyryl group of amikacin. A crystal structure of Eis in complex with coenzyme A and tobramycin revealed how tobramycin can be accommodated in the Eis active site in two binding modes, consistent with its diacetylation. These studies, describing chemical and structural details of acetylation, will guide future efforts towards designing aminoglycosides and Eis inhibitors to overcome resistance in tuberculosis.